Hammer-drill.



A. H. TAYLOR.

HAMMER DRILL.

APPLICATION FILED MAR.13, 1908,

898,702. Patented Sept. 15,1908.

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HAMMER DRILL.

APPLICATION FILED MAR.13, 1908,

898,702, Patented Sept. 15, 1908.

2 SHBETS-SHEET 2.

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UNITED STATES PATENT OFFICE.

ALBERT H. TAYLOR, OF EASTON, PENNSYLVANIA, ASSIGNOR TO INGERSOLL-RANDCOM- PANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

To all whom it may concern:

Be it known that I, ALBERT H. TAYLOR, a citizen of the United States,and resident of Easton, in the county of Northampton and State ofPennsylvania, have invented a new and useful Improvement inHammer-Drills, of which the following is a specification.

My invention consists in certain improve ments in that class ofpneumatic tools known as hammer drills, in which an air feed piston isrovided for forcing the tool forward and holding it in its workingposition. In tools of this type which are used without mountings, itfrequently happens that the distance from the rock face to be cut to therock face against which the air feed piston rests, is greater than thelength of the tool when fed to its extreme limit, thus requiring thebuilding of a temporary backing for the feed piston sufficient to holdthe tool in its working position and permit it to be forced forward toits work.

The object of my invention is to provide an adjustable extension forincreasing the length of the air feed piston which forms the rearsupport for the tool, so as to obviate the necessity of building atemporary backing.

A practical embodiment of my invention is represented in theaccompanying drawings in which Figure 1 represents the tool as in use,Fig. 2 represents a portion of the tool on an enlarged scale partiallyin side elevation and partially in longitudinal central section, with myimproved extension for the air feed piston applied thereto, thecontrolling valve being in position to close communication from the airsupply both to the air feed and to the hammer, the air feed being inopen communication with external atmosphere, Fig. 3 is a detail viewpartially in section and partially in side elevation, the controllingvalve being shown in position to open the air supply to the air feed andclose communication between the air supply and the hammer, thecommunication between the air feed and atmosphere also being shut ofl,Fig. 4 is a similar view with the controlling valve shown in position toopen communication between the air supply and both the air feed and thehammer, communication between the air Specification of Iletters Patent.

Application filed March 13, 1908.

Patented Sept. 15, 1908.

Serial No. 420,856.

feed and the atmosphere being closed, Fig. 5 is a transverse sectiontaken in the plane of the line AA of Fig. 2, looking in the direction ofthe arrows, Fig. 6 is a detail'top plan View of the locking plate, Figs.7 and 8 are detail sections showing the location of the several portswhen the valve is in the position shown in Fig. 2, Figs. 9 and 10 aredetail sections showing the location of the several ports when the valveis in the position shown in Fig. 3, and Figs. 11 and 12 are detailsections showing the location of the ports vFvhen the valve is in theposition shown in The hammer cylinder is denoted by 1, its head block by2 and its tool steel by 3. The air feed cylinder is denoted by 4 and itis attached directly to the head block 2. The hollow air feed piston,denoted by 5, telescopes within the cylinder 4 and is provided with ahead 6 which loosely fits the bore of the said cylinder. This piston isfitted to slide through a collar 7 on the rear end of the cylinder 4within which is placed a packing ring 8 and a soft packing 9 held inposition by a gland 10. This piston forms the rear support for the tool.

An adjustableextension 11 telescopes within the hollow pistolr 5, whichextension is provided with a suitable pointed rear end forengagementwith the part which forms the support for, thetool and anenlarged head at its front end for preventing the extension from fallingout of the hollow piston when released therefrom. This air feed pistonextension 11 may be locked in any desired adjustment, as follows: Therear end of the hollow piston 5 has fixed thereto a collar 12 having atapered socket 12* therethrough for receiving a wedge key 13, thetapered face of the said key bearing against the outer wall of the slotand the other face of which key bears against a gib 13* interposedbetween the key and the extension 11.

The head block 2 of the tool is provided with a hole therethrough, aportion of which forms a taper seat for the tapered portion 14 of acontrolling valve. The cylindrical portion 15 of the said valve at theend of its tapered portion, is provided with an angular portion 16 onwhich is fixed the locking plate 17 and the handle 18 of the valve,exterior to the head block. This locking plate 17 has its inner faceadjacent to the outer face of the head block and is provided with threeshallow recesses 19, 20, 21, arranged to respectively receive and retainagainst unintentional removal, the rounded end of the spring guidedsliding pin 22 mounted in the head block.

The locking plate 17 is further provided with shoulders 23, 24, arrangedto engage the rojecting end of a stop 25 on the head blocr for limitingthe rotary movement of the controlling valve in both directions.

The air supply pipe 26 is secured to the head block 2 by a collar 27having a screwthreaded engagement with the hole in the head block beyondits taper seat. The controlling valve is further provided with a chamber28 in open communication with the air supply pipe 26.

Ports 29, 30 lead from the chamber 28 to the seat in the head block.Ports 31, 32 lead respectively from the seat in the head block to theair feed chamber 33 and the hammer feed chamber 34, said portsbeing inthe same lane as the valve ports 29, 30. The valve is urther providedwith a through port 35. Ports 36, 37, in the same plane as the throuh-port 35, lead from the valve seat respectiveiy to the air feed chamber33 andto the external atmosphere.

By manipulating the valve through its handle 18, it will be seen thatthe air supply may be brought first into open communication with the airfeed chamber and secofidly into open communication with the air feedchamber and the hammer, or the supply may be out off from both thehammer and the air feed chamber. In this last position the air feedchamber is brought into open communi cation with the externalatmosphere.

In operation, when the distance from the rock face to be cut to the faceagainst which the air feed iston is to rest, is so great that the toolwou d not reach when extended to its limit, the locking key 12 of theextension 11 is released and the extension is moved rearwardly asufficient distance to bring the tool steel into position for work withthe air feed iston telescoped within its cylinder. The rey is thendriven into position to lock the extension to its piston. The valve maythen be operated to manipulate the tool and the air feed.

By providing a packing ring 8, soft packing 9 and gland 10, the air feedcylinder 4 may be made of rough material with its interior unfinished,the head 6 of the air feed piston having only such a fit within thecylinder 4 as will insure the stability of the arts. The advantage ofthis construction is that it does away with packing the piston head,which packing wears away very rapidly when used, and also will permitthe piston to travel freely within the cylinder even if the cylindershould become bent or dented as oft times happens in actual service.Furthermore, by providing the key 13 with a head 13** at its small end,the key cannot be driven entirely out of the collar 12. The gib 13' andalso the key 13, are ermanently retained in position by the attac mentof the collar 12 to the rear end of the piston 5.

While the invention has been described in connection with an air feedhammer drill, it is to be understood that any other fluid power may beutilized and any other type of tool may be employed in connection withthis invention without departing from the spirit and scope thereof.

What I claim is:

1. A neumatic tool, an air pressure feeding device therefor and anadjustable extension secured to said device, forming an end support forthe tool.

2. A pneumatic tool, an air pressure feeding device therefor comprisinga cylinder and its piston, and an adjustable piston extension forming anend support for the tool.

3. A pneumatic tool, an air pressure feeding device therefor comprisinga cylinder and its piston, an adjustable piston extension forming an endsupport for the tool, and means for locking the extension to andreleasing it from the piston.

4. A pneumatic tool, an air pressure feeding device therefor comprisinga cylinder and its hollow piston, and an adjustable extensiontelescoping Within the piston, forming an end support for the tool.

5. A pneumatic tool, an air pressure feeding device therefor comprisinga cylinder and its hollow piston, an adjustable extension telescopingwithin the piston, forming an end support for the tool, and means forlocking the extension to and releasing it from the piston.

6. A pneumatic tool, an air pressure feeding device therefor comprisinga cylinder and a piston having its head loosely fitting the bore of thecylinder, a pressure tight joint between the rear end of the cylinderand the iston, an adjustable piston extension forming an end support forthe tool and means for locking the extension to and releasing it fromthe piston.

7. A pneumatic tool, an air pressure feeding device thereforCODlPIlSlIlgjLQfllglQILittached directly to the to ol, a piston fittedto slide within thefidiiider ang l a wadll table piston extensionforming an end s upp ort'fo;r

" 8. A pneumatic tool, an air pressure feeding device thereforcomprising a cylinder attached directly to thetool, a hollow pistonfitted to slide in the cylinder, an adjustable my invention, I havesigned my name in extension telescoping Within the piston forlnpresenceof two Witnesses, this eleventh day ing an end support for the tool andmeans for of March 1908.

locking the extension to and releasing it from ALBERT H. TAYLOR. 5 thepiston comprising a gib engaging the eX- Witnesses:

tension and a wedge key engaging the gib. RUssELL H. WILHELM,

In testimony, that I claim the foregoing as WARD RAYMOND.

